Hazard Alert: Lockout/Tagout

Summary Statement

Describes the dangers of not following lockout/tagout procedures and discusses the steps that should be taken in these situations.
2002

Dozens of construction
workers are killed every year because they did not de-energize equipment
or lock it out before working on it. Most of the deaths are electrocutions,
but workers sometimes are crushed or have amputations or other injuries.
These types of energy need to be controlled: electric, hydraulic, pneumatic,
mechanical, and pressurized liquids, vapors, and gases.

Protect
Yourself

Lockout/tagout
is a way to make sure electricity or other energy is not turned on (or
released) while someone is working on machinery. Turning off a power
switch is not enough. You must de-energize (prevent equipment
from starting or moving), lock it out, release stored energy (for
instance, bleed air from a pneumatic hose), and test to make sure the
energy is off.

Your employer should:

Set up a written
lockout/tagout program

Train you to
use the program.*

The program should
cover:

Planning to identify:

energy sources

workers who
can get hurt

who will
de-energize equipment (and how).

Keeping track
of all involved workers

Telling workers
on new shifts about the lockout/tagout job

Making sure the
equipment is de-energized so it cannot be restarted

Setting and removing
lockout/tagout devices

Coordinating
with other jobs under way

Releasing stored
energy (for instance, discharging capacitors)

Returning equipment
to service (including testing or positioning of equipment).

Lockout/Tagout
Procedure

1. Notification.
Tell equipment operators and supervisors that power is being disconnected
or isolated.
2. Preparation. Check with your supervisor for a written procedure
(or checklist) that tells how to shut down and restart the equipment you
are working on.
3. Shutdown. Turn off the equipment.
4. Isolation. Separate all energy sources using proper isolating
devices – like manual circuit breakers or disconnect switches. Pushbuttons
or selector switches cannot be the only way to de-energize. A lot of equipment
has more than one type of energy that needs to be isolated.
5. Lockout/tagout application. Every worker who can be exposed
to hazardous energy must be part of the lockout/tagout process.
––––––
*OSHA has a comprehensive standard for lockout/tagout for general industry
(29CFR1910.147), but not for construction.

A lockout
device is a key or combination lock with a special tag with a worker's
name. The lock must be attached to an isolating device, circuit breaker,
and/or switch to prevent turning on the energy source or equipment or
releasing energy.

A tagout device
is a tag and a way to attach it that can withstand at least 50 pounds
of force. (Some tagout devices are attached with wire.) Use a tagout
device only when you cannot lock out. The tag should have a label or
sign that says no one can turn on the equipment or remove the energy-isolating
device without permission. (OSHA allows tagout devices, but the National
Institute for Occupational Safety and Health, NIOSH, does not recommend
tagout-only work.)

Each worker
at risk should apply an individual lockout/tagout device to each
source of hazardous energy – so there may be many locks or tags
on each device. You must be the only one who has the key or combination
for a lockout device you install – except in complex lockout/tagout
(read below).

Individual qualified
employee control. For minor servicing, maintenance, or inspection of
plug-and-cord equipment, you may work without attaching lockout/tagout devices
if you unplug the equipment and you always work next to the power
plug and control the plug. Complex lockout/tagout. A special written plan is needed when a job
has more than one of any of these:

Energy source

Crew

Craft

Location

Employer

Way to isolate
energy, or

Work shift.
One crew member should be in charge of the whole lockout/tagout. This
person should be trained and identified by name in the written plan.
Each worker still should check to be sure all energy sources are locked
out before starting work.

6. Control of stored
energy. Release energy by discharging capacitors, removing jacks or
chock blocks, or draining hydraulic lines, for instance.
7. Verification. Use testing equipment (such as an electric circuit
tester) to make sure equipment has been de-energized.
8. Removal of lockout/tagout devices. Only the worker who puts on
a lockout or tagout device should take it off. If someone else must take
off the device, he/she must be sure that the person who installed it is
not on the site, and must warn that employee when he/she returns.
9. Return to service. When the work is done and lockout/tagout devices
are off, you must test and look to be sure all tools, mechanical
restraints, and electrical devices have been removed before you turn on
power. Before you re-energize, you must warn all workers who can
operate the equipment and make sure no one else is near it.
10. Temporary release. If the job requiring lockout/tagout is interrupted
for testing or positioning equipment, the procedures must start all over.